First measurements of 222Rn and 220Rn activities in soil in Taylor Valley, Antarctica.

Warming global climate threatens the stability of the polar regions and may result in cascading broad impacts. Studies conducted on permafrost in the Arctic regions indicate that these areas may store almost twice the carbon currently present in the atmosphere. Therefore, permafrost thawing has the potential to magnify the warming effect by doubling the more direct anthropogenic impact from burning of fossil fuels, agriculture and changes in land use. . Permafrost thawing may also intensify the Rn transport due to the increase of fluid saturation and permeability of the soil. A detailed study of 222Rn and 220Rn activity levels in polar soils constitutes a starting point to investigate gas migration processes as a function of the thawing permafrost. Although several studies have been carried out in the Arctic regions, there is little data available from the Southern Hemisphere. The Italian &#8211; New Zealand &#8220;SENECA&#8221; project aims to fill this gap and to provide the first evaluations of gas concentrations and emissions from permafrost and/or thawed shallow strata of the Taylor Valley, Antarctica. Taylor Valley is one of the few Antarctic regions that are not covered by ice and therefore is an ideal target for permafrost investigations. Results from our first field observations highlight very low values for 222Rn (mean 621 Bq m-3, max value 1,837 Bq m-3) and higher values for 220Rn (mean 11,270 Bq m-3, max value 27,589 Bq m-3), suggesting a shallow source. These measured activity values are essentially controlled by the radionuclide content in the soil, by the permeability and porosity of the soil, and by the water content. This dataset also represents an important benchmark for future measurements to track the melt progress of Antarctic permafrost.

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SourcE and impact of greeNhousE gasses in AntarctiCA: the Seneca project

10.5194/egusphere-egu2020-1431 ◽

2020 ◽

Author(s):

Livio Ruggiero ◽

Alessandra Sciarra ◽

Adriano Mazzini ◽

Claudio Mazzoli ◽

Valentina Romano ◽

...

Keyword(s):

Global Climate ◽

The Arctic ◽

Polar Regions ◽

Dry Valleys ◽

Global Climate Changes ◽

Greenhouse Gasses ◽

Arctic Regions ◽

Geological Discontinuities ◽

The Stability ◽

Shallow Strata

Current global climate changes represent a threat for the stability of the polar regions and may result in cascading broad impacts. Studies conducted on permafrost in the Arctic regions indicate that these areas may store almost twice the carbon currently present in the atmosphere. Therefore, permafrost thawing may potentially cause a significant increase of greenhouse gases concentrations in the atmosphere, exponentially rising the global warming effect. Although several studies have been carried out in the Arctic regions, there is a paucity of data available from the Southern Hemisphere. The Seneca project aims to fill this gap and to provide a first degree of evaluations of gas concentrations and emissions from permafrost and/or thawed shallow strata of the Dry Valleys in Antarctica. The Taylor and Wright Dry Valleys represent one of the few Antarctic areas that are not covered by ice and therefore represent an ideal target for permafrost investigations.Here we present the preliminary results of a multidisciplinary field expedition conducted during the Antarctic summer in the Dry Valleys, aimed to collect and analyse soil gas and water samples, to measure CO2 and CH4 flux exhalation, to investigate the petrological soil properties, and to acquire geoelectrical profiles. The obtained data are used to 1) derive a first total emission estimate for methane and carbon dioxide in this part of the Southern Polar Hemisphere, 2) locate the potential presence of geological discontinuities that can act as preferential gas pathways for fluids release, and 3) investigate the mechanisms of gas migration through the shallow sediments. These results represent a benchmark for measurements in these climate sensitive regions where little or no data are today available.

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Pollutants present in different components of the Svalbard archipelago environment / Zanieczyszczenia obecne w różnych komponentach środowiska archipelagu Svalbard

Ecological Chemistry and Engineering S ◽

10.2478/v10216-011-0040-9 ◽

2012 ◽

Vol 19 (4) ◽

pp. 571-584 ◽

Cited By ~ 8

Author(s):

Marek Ruman ◽

Katarzyna Kozak ◽

Sara Lehmann ◽

Krystyna Kozioł ◽

Żaneta Polkowska

Keyword(s):

Measurement Data ◽

Geographic Location ◽

Analytical Techniques ◽

The Arctic ◽

Polar Regions ◽

Negative Effects ◽

Svalbard Archipelago ◽

Arctic Ecosystem ◽

Arctic Regions ◽

Area Of Interest

Abstract During last years an interest in the processes of transport and fate of pollutants to the polar regions located distantly from industrial centers, has significantly increased. The current analytical techniques enabling conducting studies prove that the Arctic regions (in the past considered as a pollution free area) have become an area of highly intensive anthropopresion. Svalbard archipelago stands out from the other polar regions due to its specific environmental conditions and geographic location, which results in becoming a reservoir of contamination in this area. Systematic environmental monitoring of arctic regions is extremely important due to an unique opportunity of observing a direct impact of pollution on the ongoing processes in the area of interest. In this way measurement data obtained are a valuable source of information, not only on changes occurring in the Arctic ecosystem, but also on estimated global impact of certain xenobiotics present in the environment. Furthermore, qualitative and quantitative studies on particular chemicals deposited in different regions of the Arctic ecosystem may constitute the basis for undertaking actions aimed at preventing negative effects caused by these pollutants.

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September Arctic Sea Ice minimum prediction – a new skillful statistical approach

10.5194/esd-2018-61 ◽

2018 ◽

Author(s):

Monica Ionita ◽

Klaus Grosfeld ◽

Patrick Scholz ◽

Renate Treffeisen ◽

Gerrit Lohmann

Keyword(s):

Sea Ice ◽

Statistical Model ◽

Climate Models ◽

Global Climate ◽

Arctic Sea Ice ◽

The Arctic ◽

Polar Regions ◽

Sea Ice Extent ◽

Important Indicator ◽

Predictive Skill

Abstract. Sea ice in both Polar Regions is an important indicator for the expression of global climate change and its polar amplification. Consequently, a broad interest exists on sea ice coverage, variability and long term change. However, its predictability is complex and it depends on various atmospheric and oceanic parameters. In order to provide insights into the potential development of a monthly/seasonal signal of sea ice evolution, we developed a robust statistical model based on oceanic and different atmospheric variables to calculate an estimate of the September sea ice extent (SSIE) on monthly time scale. Although previous statistical attempts of monthly/seasonal SSIE forecasts show a relatively reduced skill, when the trend is removed, we show here that the September sea ice extent has a high predictive skill, up to 4 months ahead, based on previous months' atmospheric and oceanic conditions. Our statistical model skillfully captures the interannual variability of the SSIE and could provide a valuable tool for identifying relevant regions and atmospheric parameters that are important for the sea ice development in the Arctic and for detecting sensitive and critical regions in global coupled climate models with focus on sea ice formation.

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Hemispheric sea ice extent dynamics as observed from MSMR

MAUSAM ◽

10.54302/mausam.v60i3.1101 ◽

2021 ◽

Vol 60 (3) ◽

pp. 295-308

Author(s):

NILAY SHARMA ◽

M. K. DASH ◽

P. C. PANDEY ◽

N. K. VYAS

Keyword(s):

Sea Ice ◽

Global Climate ◽

Ice Cover ◽

The Arctic ◽

Ice Formation ◽

Spatial And Temporal Variation ◽

Polar Regions ◽

Sea Ice Extent ◽

Year 2000 ◽

Formation Phase

The ice covered regions of the polar seas influence the global climate in several ways. Any perturbation in the polar oceanic cryosphere affects the local weather and the global climate through modulation of the radiative forcing, the bottom water formation and the mass & the momentum transfer between Atmosphere-Cryosphere-Ocean System. The cold, harsh and inhospitable conditions in the polar regions prohibit the collection of extensive in situ data with sufficient spatial and temporal variation. However, satellite remote sensing is an ideal technique for studying the areas like the polar regions with synoptic and repetitive coverage. This paper discusses the analysis of the data obtained over the polar oceanic regions during the period June 1999 – September 2001 through the use of Multi-channel Scanning Microwave Radiometer (MSMR), onboard India’s first oceanographic satellite Oceansat-1. The MSMR observation shows that all the sectors in the Antarctic behave differently to the melting and formation of the sea ice. Certain peculiar features like the increase in sea ice extent during the melt season of 1999 – 2000 in the Indian Ocean sector, 15 – 20% decrease in the sea ice extent in the western Pacific sector during the ice formation period for the year 2000, melting spell within the formation phase of sea ice in B & A sector in the year 2000 were observed. On the other hand the northern polar sea ice extent is seen to be more dominated by the land characteristics. The ice formation in Kara and the Barent Sea sector is dominated by the ocean currents, where as the ice covered in the Japan and the Okhotsk Sea is dominated by the land processes. The sea ice extent in the Arctic Ocean show fluctuations from July to October and remain almost steady over other months. The global sea ice cover shows a formation phase from March to June and melting phase from November to February. In other months, i.e., from July – October the global sea ice cover is dominated by the hemispheric asymmetry of the ice growth and retreat.

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Surface reflectivity in polar regions retrieved from TDS-1 mission data

10.5194/egusphere-egu21-13036 ◽

2021 ◽

Author(s):

Frederik Kreß ◽

Maximilian Semmling ◽

Estel Cardellach ◽

Weiqiang Li ◽

Mainul Hoque ◽

...

Keyword(s):

Remote Sensing ◽

Surface Roughness ◽

Sea Ice ◽

Large Scale ◽

Global Climate ◽

Path Loss ◽

Signal Strength ◽

Global Navigation Satellite Systems ◽

The Arctic ◽

Polar Regions

In current times of a changing global climate, a special interest is focused on the large-scale recording of sea ice. Among the existing remote sensing methods, bi- statically reflected signals of Global Navigation Satellite Systems (GNSS) could play an important role in fulfilling the task. Within this project, sensitivity of GNSS signal reflections to sea ice properties like its occurrence, sea ice thick- ness (SIT) and sea concentration (SIC) is evaluated. When getting older, sea ice tends go get thicker. Because of decreasing salinity, i.e. less permittivity, as well as relatively higher surface roughness of older ice, it can be assumed that reflected signal strength decreases with increasing SIT. The reflection data used were recorded in the years 2015 and 2016 by the TechDemoSat-1 (TDS-1) satellite over the Arctic and Antarctic. It includes a down-looking antenna for the reflected as well as an up-looking antenna dedicated to receive the direct sig- nal. The raw data, provided by the manufacturer SSTL, were pre-processed by IEEC/ICE-CSIC to derive georeferenced signal power values. The reflectivity was estimated by comparing the power of the up- and down-looking links. The project focuses on the signal link budget to apply necessary corrections. For this reason, the receiver antenna gain as well as the Free-Space Path Loss (FSPL) were calculated and applied for reflectivity correction. Differences of nadir and zenith antenna FSPL and gain show influence of up to 6 dB and &#8722;9 dB to 9 dB respectively on the recorded signal strength. All retrieved reflectivity values are compared to model predictions based on Fresnel coefficients but also to avail- able ancillary truth data of other remote sensing missions to identify possible patterns: SIT relations are investigated using Level-2 data of the Soil Moisture and Ocean Salinity (SMOS) satellite. The SIC comparison was done with an AMSR-2 product. The results show sensitivity of the reflectivity value to both SIT and SIC simultaneously, whereby the surface roughness is also likely to have an influence. This on-going study aims at the consolidation of retrieval algorithms for sea-ice observation. The resolution of different ice types and the retrieval of SIT and SIC based on satellite data is a challenge for future work in this respect.

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Causes and consequences of Southern Ocean change: the IPCC SROCC assessment

10.5194/egusphere-egu2020-164 ◽

2020 ◽

Author(s):

Michael Meredith ◽

Martin Sommerkorn ◽

Sandra Cassotta ◽

Chris Derksen ◽

Alexey Ekaykin ◽

...

Keyword(s):

Southern Ocean ◽

Sea Ice ◽

Sea Level ◽

Ocean Circulation ◽

Global Climate ◽

Ice Sheets ◽

The Arctic ◽

Polar Regions ◽

Ice Shelves

Climate change in the polar regions exerts a profound influence both locally and over all of our planet.&#160; Physical and ecosystem changes influence societies and economies, via factors that include food provision, transport and access to non-renewable resources.&#160; Sea level, global climate and potentially mid-latitude weather are influenced by the changing polar regions, through coupled feedback processes, sea ice changes and the melting of snow and land-based ice sheets and glaciers.Reflecting this importance, the IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) features a chapter highlighting past, ongoing and future change in the polar regions, the impacts of these changes, and the possible options for response.&#160; The role of the polar oceans, both in determining the changes and impacts in the polar regions and in structuring the global influence, is an important component of this chapter.With emphasis on the Southern Ocean and through comparison with the Arctic, this talk will outline key findings from the polar regions chapter of SROCC. It will synthesise the latest information on the rates, patterns and causes of changes in sea ice, ocean circulation and properties. It will assess cryospheric driving of ocean change from ice sheets, ice shelves and glaciers, and the role of the oceans in determining the past and future evolutions of polar land-based ice. The implications of these changes for climate, ecosystems, sea level and the global system will be outlined.

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The Timing of Initial Spring Melt in the Arctic from Nimbus-7 SMMR Data (Abstract)

Annals of Glaciology ◽

10.3189/s0260305500000811 ◽

1987 ◽

Vol 9 ◽

pp. 244-244

Author(s):

Mark R. Anderson

Keyword(s):

Sea Ice ◽

Large Scale ◽

Chukchi Sea ◽

Global Climate ◽

Arctic Basin ◽

Temporal Variations ◽

The Arctic ◽

Energy Budgets ◽

Polar Regions ◽

Ice Surface

The ablation of sea ice is an important feature in the global climate system. During the melt season in the Arctic, rapid changes occur in sea-ice surface conditions and areal extent of ice. These changes alter the albedo and vary the energy budgets. Understanding the spatial and temporal variations of melt is critical in the polar regions. This study investigates the spring onset of melt in the seasonal sea-ice zone of the Arctic Basin through the use of a melt signature derived by Anderson and others from the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) data. The signature is recognized in the “gradient ratio” of the 18 and 37 GHz vertical brightness temperatures used to distinguish multi-year ice. A spuriously high fraction of multi-year ice appears rapidly during the initial melt of sea ice, when the snow-pack on the ice surface has started to melt. The brightness-temperature changes are a result of either enlarged snow crystals or incipient puddles forming at the snow/ice interface.The timing of these melt events varies geographically and with time. Within the Arctic Basin, the melt signatures are observed first in the Chukchi and Kara/Barents Seas. As the melt progresses, the location of the melt signature moves westward from the Chukchi Sea and eastward from the Kara/Barents Seas to the Laptev Sea region. The timing of the melt signal also varies with year. For example, the melt signature occurred first in the Chukchi Sea in 1979, while in 1980 the signature was first observed in the Kara Sea.There are also differences in the timing of melt for specific geographic locations between years. The melt signature varied almost 25 days in the Chukchi Sea region between 1979 and 1980. The other areas had changes in the 7–10 day range.The occurrence of these melt signatures can be used as an indicator of climate variability in the seasonal sea-ice zones of the Arctic. The timing of the microwave melt signature has also been examined in relation to melt observed on short-wave imagery. The melt events derived from the SMMR data are also related to the large-scale climate conditions.

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Consistent Comparison of Remotely Sensed Sea Ice Concentration Products with ERA-Interim Reanalysis Data in Polar Regions

Remote Sensing ◽

10.3390/rs12182880 ◽

2020 ◽

Vol 12 (18) ◽

pp. 2880

Author(s):

Shuang Liang ◽

Jiangyuan Zeng ◽

Zhen Li ◽

Dejing Qiao ◽

Ping Zhang ◽

...

Keyword(s):

Climate Change ◽

Sea Ice ◽

Global Climate ◽

Remotely Sensed ◽

The Arctic ◽

Polar Regions ◽

Sea Ice Concentration ◽

Sea Ice Extent ◽

Climate Change Research ◽

Ice Concentration

Sea ice concentration (SIC) plays a significant role in climate change research and ship’s navigation in polar regions. Satellite-based SIC products have become increasingly abundant in recent years; however, the uncertainty of these products still exists and needs to be further investigated. To comprehensively evaluate the consistency of the SIC derived from different SIC algorithms in long time series and the whole polar regions, we compared four passive microwave (PM) satellite SIC products with the ERA-Interim sea ice fraction dataset during the period of 2015–2018. The PM SIC products include the SSMIS/ASI, AMSR2/BT, the Chinese FY3B/NT2, and FY3C/NT2. The results show that the remotely sensed SIC products derived from different SIC algorithms are generally in good consistency. The spatial and temporal distribution of discrepancy among satellite SIC products for both Arctic and Antarctic regions are also observed. The most noticeable difference for all the four SIC products mostly occurs in summer and at the marginal ice zone, indicating that large uncertainties exist in satellite SIC products in such period and areas. The SSMIS/ASI and AMSR2/BT show relatively better consistency with ERA-Interim in the Arctic and Antarctic, respectively, but they exhibit opposite bias (dry/wet) relative to the ERA-Interim data. The sea ice extent (SIE) and sea ice area (SIA) derived from PM and ERA-Interim SIC were also compared. It is found that the difference of PM SIE and SIA varies seasonally, which is in line with that of PM SIC, and the discrepancy between PM and ERA-Interim data is larger in Arctic than in Antarctic. We also noticed that different algorithms have different performances in different regions and periods; therefore, the hybrid of multiple algorithms is a promising way to improve the accuracy of SIC retrievals. It is expected that our findings can contribute to improving the satellite SIC algorithms and thus promote the application of these useful products in global climate change studies.

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Surface Freshwater Fluxes in the Arctic and Subarctic Seas during Contrasting Years of High and Low Summer Sea Ice Extent

Remote Sensing ◽

10.3390/rs13081570 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1570

Author(s):

Sarah B. Hall ◽

Bulusu Subrahmanyam ◽

Ebenezer S. Nyadjro ◽

Annette Samuelsen

Keyword(s):

Sea Ice ◽

Global Climate ◽

Sea Surface ◽

Sea Surface Salinity ◽

The Arctic ◽

Spatial And Temporal Variability ◽

Polar Regions ◽

Surface Salinity ◽

Sea Ice Concentration ◽

Sea Ice Extent

Freshwater (FW) flux between the Arctic Ocean and adjacent waterways, predominantly driven by wind and oceanic currents, influences halocline stability and annual sea ice variability which further impacts global circulation and climate. The Arctic recently experienced anomalous years of high and low sea ice extent in the summers of 2013/2014 and 2012/2016, respectively. Here we investigate the interannual variability of oceanic surface FW flux in relation to spatial and temporal variability in sea ice concentration (SIC), sea surface salinity (SSS), and sea surface temperature (SST), focusing on years with summer sea–ice extremes. Our analysis between 2010–2018 illustrate high parameter variability, especially within the Laptev, Kara, and Barents seas, as well as an overall decreasing trend of FW flux through the Fram Strait. We find that in 2012, a maximum average FW flux of 0.32 × 103 ms−1 in October passed over a large portion of the Northeast Atlantic Ocean at 53°N. This study highlights recent changes in the Arctic and Subarctic Seas and the importance of continued monitoring of key variables through remote sensing to understand the dynamics behind these ongoing changes. Observations of FW fluxes through major Arctic routes will be increasingly important as the polar regions become more susceptible to warming, with major impacts on global climate.

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Japan and 100 Years of Antarctic Legal Order: Any Lessons for the Arctic?

The Yearbook of Polar Law Online ◽

10.1163/2211-6427_002 ◽

2015 ◽

Vol 7 (1) ◽

pp. 1-54

Author(s):

Akiho Shibata

Keyword(s):

Learning Processes ◽

Legal Order ◽

The Arctic ◽

Polar Regions ◽

Mutual Learning ◽

Arctic Regions ◽

End Products ◽

International Legal Order ◽

History Of ◽

The Antarctic

This paper examines whether core foundational principles can be distilled from the 100 years of history of the legal order-making in the polar regions. Despite differences in geo-physical, socio-historical, and legal circumstances conditioning the Antarctic and the Arctic regions, the examination of the processes of legal order-making in both polar regions demonstrates that there are some foundational principles being assessed and applied in designing their respective legal regimes. The identification of those core foundational principles would not necessarily lead to similar end products, nor would such examination necessarily advocate, for example, an Arctic Treaty System. This paper, instead, submits that between the Antarctic and the Arctic there are mutual learning processes already discernible at the foundational level of process legitimacy in international legal order-making. This examination also provides a broader framework to assess the existing literature that sees certain interactions between the two regimes at the level of substantive principles and rules.

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